It's insanely difficult to excel at League of Legends, t he world's most popular competitive video game. Only a select few can handle the pro-level regimen required to gain the extensive game knowledge and elite mechanical skills and reflexes to compete.

Team Liquid players practice together for eight hours a day, scrimmaging against other pro and Challenger-level teams. In the hours before and after that team practice, they play on their own for nearly every waking minute.

They eat their lunch and dinner — usually takeout — while they discuss game strategy and review videos of previous matches with their coach and team analyst. When they get home from the team's training facility, a small office in a Santa Monica office park, players almost immediately hop on the computer to play "Solo Queue," a game mode that matches you with other random players at your skill level.

Diego "Quas' Ruiz gets in last minute practice before his professional match later that day.
Harrison Jacobs/Business Insider

Some players, like Ruiz, take time out to video-chat with family members or relax with girlfriends. However, others do nothing but play the game — which changes every few months to introduce new strategies and wrinkles for players to master.

Chae “Piglet” Gwang-jin (furthest left) was a member of Korean team SK Telecom T1, when they won the League of Legends World Championship in 2013.
AP Photo/Mark J. Terrill,File)

Ruiz's two Korean teammates, Chae "Piglet" Gwan-jin and Kim "Fenix" Jae-hun, are notorious for pushing the physical boundaries for how much a person can practice. They often sleep only four hours a night and practice between 12 and 14 hours per day.

Their regimen is more extreme than most North American players, but it's common for those from Korea, the epicenter of competitive gaming.

For a time, this past season, the Korean players' schedule worried other players on the team, who felt their intense schedule was making them less effective.

"[Chae and Kim] don't stop practicing. They are crazy like that," says Team Liquid teammate Alex "Xpecial" Chu, a 22-year-old California native who has played in the pro leagues for four years.

He says his Korean colleagues practice "25 hours a day," but the two Korean teammates have their reasons for trying to practice harder than everybody else.

"If someone [in the US] plays 30 games a week — that's just a random number — a Korean would play 70-80 games. Take that difference over a week, over a month, over years, and that's going to be a huge difference," Chae told Business Insider, through a translator.

Ruiz, on the other hand, says he values "quality over quantity" when it comes to practice. However, his training only sounds marginally less intense.

"I don't play game after game after game. I play a game, take a five-minute break, take a walk around, and then play again," Ruiz says.

Team Liquid co-owner Steve Arhancet observes the team's daily scrimmages.
Harrison Jacobs/Business Insider
While in season from January through August, the team follows their training schedule Tuesday through Friday and plays matches on Saturdays and Sundays.

"I can technically see friends and family on Monday, our day off," Chu explains. "But because of the way League of Legends works, there is no downtime. I don't want to spend my time away from here … I'd rather spend my time practicing."

Even in the "off-season" from August through December, the players are still practicing relentlessly. Even a month's break can hurt your performance, according to Chu.

"Even when you are in the off season … you have to practice," Chu says. "I'm not satisfied with being anything below first, so I work my hardest the whole time."